Device for unwinding thread windings

ABSTRACT

A device for unwinding thread windings which are axially slipped on a winding support whose diameter is variable and is mounted on a rotatably mounted shaft carrying at one end a slidable cone engaging heads on one end of a plurality of legs which extend parallel to the axis of the rotatable shaft and are forming the expandable body of the winding support. Each leg is pivotally connected adjacent its ends with the outer ends of two parallel arms, the other inner ends of which are pivotally connected to collars on the rotatable shaft. A spring urges the slidable cone in a direction in which it engages the heads on the legs and moves the same outwardly together with the legs to the desired diameter so as to frictionally engage and grip the inner cylindrical surface of the thread winding to be unwound.

United States Patent 1191 Moor 1111 3,820,736 1 June 28, 1974 1 1 DEVICE FOR UNWINDING THREAD WINDINGS [75] Inventor: Wilhelm Moor, Emmenbrucke,

Switzerland 22 Filed: Feb. 15, 1972 21 Appl. No; 226,601

[30] Foreign Application Priority Data Feb. 18, 1971 Switzerland 2346/71 [52 US. Cl. 242/110.'2,242/72.1v 51 Int. Cl. B65h 75/24 [58] Field of Search 242/110.1, 110.2, 110.3,

1l8.5,,ll8.6, 128,54 11,1'10' 2,339,543 l/l944 Bishop 242/72 X 2,678,175 5/1954 Wiig 242/110.2 2,971,721 2/1961 Jones....

3,128,060 4/1964 Todd 242/110.]

Primary Examiner-George F. Mautz Attorney, Agent, or Firm-l-lill, Gross, Simpson, Van Santen, Steadman, Chiara & Simpson 5 7] ABSTRACT A device for unwinding thread windings which are axially slipped on a winding support whose diameter is variable and is mounted on a rotatably mounted shaft carrying at one end a slidable cone engaging heads on one end of a plurality of legs which extend parallel to the axis of the rotatable shaft and are forming the expandable body of the winding support. Each leg is pivotally connected adjacent its ends with the outer ends of two parallel arms, the other inner ends of which are pivotally connected to collars on the rotatable shaft. A spring urges the slidable cone in a direction in which it engages the heads on the legs and moves the same outwardly together with the legs to the desired diameter so as to frictionally engage and grip the inner cylindrical surface of the thread winding to be unwound.

5 Claims, 9 Drawing; Figures PMENTEDJUHN 1274 SHEET 1 OF 5 iiliwfilv? PATENTEU I974 3.820 7 36 SHEET 3 UF 5 DEVICE FOR UNWINDING THREAD WINDINGS The invention relates to a device for unwinding thread windings which is provided with a rotatably mounted shaft which carries at one of its ends a cone provided with slide means for engaging slide heads provided on a winding support of variable diameter, and provided with a spring acting in a direction in which the diameter of the winding support is increased.

In a known unwinding device of this type the winding support comprises a zigzag shaped spring wire forming the circumference of a cylinder and in which the reversing points of the spring wire constitutes slide heads which at one end of the winding support slidably engage guides provided in a spring loaded ocne, while at the other end the reversing points of the spring wire slidably engages guides in an oppositely disposed cone. For attachment of the thread winding to this elastic winding support whose diameter is variable it is necessary to remove first the cone in order to be able to slide on the thread winding, whereupon the removed cone has to be attached again so that the thread winding comes to lie between the two cones.

It is an object of the invention to eliminate these manipulations which are necessary for replacing the thread windings on the winding device. In accordance with the invention the unwinding device is provided with a winding support having at one of its ends slidable heads provided with legs which form each one side of a linkage parallelogram in which the mentioned legs extend parallel to the axis of the unwinding device.

One embodiment of the unwinding device of the invention is particularly advantageous in that the supporting shaft comprises a tubular shaft supported by ball bearings on a stationary inner shaft and which is provided with a free end opposite the one having slide heads. The advantage is that for the purpose of attaching the thread windings to the winding support it is not necessary to remove any portion of the unwinding mechanism.

The accompanying drawing illustrates a plurality of embodiments of the unwinding device of the invention.

IN THE DRAWINGS FIG. 1 illustrates a longitudinal section of the unwinding device taken along the broken line 1 1 of FIG. 2. The upper and lower halves of this FIG. 1 illustrate two different positions of the device.

FIG. 2 illustrates a cross-sectional view taken along the broken line 2 2 of FIG. 1.

FIG. 3 illustrates in section a portion of a first modification of the unwinding device substantially along the broken line 3 3 of FIG. 4.

FIG. 4 illustrates an end elevational view taken in the FIG. 9 illustrates a longitudinal sectional view of still another modification of the unwinding device of the invention.

Referring to FIGS. 1 and 2, the illustrated unwinding device is provided with a tubular shaft 1, both ends of which have attached thereto a bearing body 2 and 3 respectively, arranged between shoulders 4 and 5 and secured in position by snap rings 6 and 7. The bearing bodies 2 and 3 contain each a ball bearing 8 and 9 respectively, which are used to mount the tubular shaft 1 on a stationary shaft 10 of the unwinding machine. For the purpose of slipping a thread winding on the machine, a three-part winding support 11 is provided which has three legs 12,, 12 12,, arranged circumferentially apart around the tubular shaft 1 and also parallel to the axis of rotation of the shaft whereby the radial distance of these parallellegs 12,, 12 12 from the tubular shaft 1 is variable. Each of these legs is pivotally connected by two pins 13 and 14 to one end of the arms 15 and 16 respectively. The other ends of these legs are connected by pins 17 and 18, respectively with projections 19 and 20 on the bearing body 3 and the hub 21, respectively. The hub 21 is mounted on the tubular shaft with some clearance between an annular shoulder 22 and a spring snap ring 23. In this manner one will realize that each leg 12,, 12 12 forms one longitudinal side of a linkage parallelogram designated by 1, 15, 12,, 16, whereby the dash and dotted side 1 of one linkage parallelogram is arranged parallel to the leg 12, and to the tubular shaft 1. The legs 12,, 12 12 will always be disposed parallel to the tubular shaft 1 and the above mentioned clearance of the hub 21 permits a compensation of minor inaccuracies in the axial dimension of the thread winding sleeves, on which the thread windings have been wound. In FIG. 1 the right hand endsof the horizontal legs 12,, 12 12 are somewhat deflected toward the center axis of the tubular shaft 1 in order to facilitate the slip-on of the thread windings. The rear or left hand ends of the legs 12,, 12 12,, are shaped to form slide heads 24 which slidably engage the bottom of grooves 25 in the cone 26. The cone 26 is provided with a hub 27 in which the tubular shaft 1 is axially slidable. Between one end of the hub 27 and the bearing body 2 is arranged a helical pressure spring 28 which is concentrically disposed about the axis of the shaft 1 and which with one end engages an annular groove 29 provided in the cone 26 while its other end is received by a cup member 30 fixedly attached to the bearing body 2. The spring 28 has the tendency to urge the cone 26 toward the hub 21 and thereby urges the slide heads 24, which engage the grooves 25, outwardly and this has the result that the linkage parallelogram 1', 15, 12 and 16 is spread apart. At the outer end of the cone 26 is arranged a stop flange 31 so that the slide heads 24 can not move outwardly of the grooves 25. In the lower half of FIG. 1 the cone 26 is illustrated in a position in which the three-part winding support 11 has its greatest diameter, while in the: upper half of FIG. 1 the cone 26 is illustrated in a position in which the mentioned winding support 11 has its smallest diameter. Accordingly, the leg 12, has in FIGS. 1 and 2, the greatest distance from the tubular shaft 1, while the two other legs 12,, 12 have the smallest radial distance from the tubular shaft 1.

The thread windings which for the purpose of unwinding the thread therefrom are to he slipped on the winding support may be provided with a tubular core or a sleeve acting as a core. Such a sleeve may consist of wire on which the thread winding has been wound and has already been subjected to a prior treatment, for instance a dyeing treatment. One may slidably attach such a winding sleeve without any further manipulation directly on the winding support whose legs 12 due to the action of the spring 28 are disposed in a spreaded position. When the winding sleeve is pushed on this winding support the legs 12 are pressed inwardly so as to correspond to the inner diameter of this winding sleeve and then the legs, which remain under the action of the spring 28, maintain the necessary friction or pressure for holding the winding sleeve on which the threadhas been wound automatically in the desired position. Contrary to the known unwinding devices it is not at all necessary when desiring to attach a thread winding on the winding device to remove any part of the device and then assemble it again after the thread winding has been put into operative position. In accordance with the invention it is even possible to slip a thread winding on the winding support 11 if the thread winding is not provided with a sleeve serving as a core. It is, however, advisable to press the winding support somewhat together during the slidable attachment of the thread winding onto the legs 12, perhaps by means of a cone or another element which is applied to the inwardly curved ends 23 of the legs 12. At the end of the unwinding operation it is known that the inner diameter of a sleeveless thread winding increases somewhat since the legs 12 are under the pressure of the spring 28 which urges the legs 12 outwardly so as to assume a larger inner diameter, the more so since the legs are under radial pressure directed against the inner wall of the thread winding. In order to avoid that in the device illustrated in FIGS. 1 and 2 the profile of the thread winding does not loose its original circular form during the unwinding of the thread because the winding support engages the inner diameter of the thread winding only at three points, it is recommended that when sleeveless thread windings are to be unwound that the unwinding device be provided with more than three legs, for instance, five or six legs.

In the modification of the device of the invention illustrated in FIGS. 3 and 4 the difference between this modified construction and the construction according to FIGS. 1 and 2 resides only in this, that an additional conical stop ring 32 is provided which in a manner not particularly illustrated in the drawing is attached to the edge of the larger stop flange 31. The ring 32 may for instance be pushed into the same. The slide heads 24 of the legs 12 are then no longer positioned in the rest position of the device in engagement with the stop flange 31 but they are engaging stop ring 32 which forms a projection of the flange 31 and the maximum diameter of the winding support 11 is correspondingly smaller. This stop ring 32 may be replaced by other stop rings having different interior diameters and one selects always an interior diameter which is only a few mm., for instance 4 to' 5 mm. greater than the interior diameter of the winding sleeve of the thread winding. When one applies this sleeve onto the winding support 11 the diameter of the latter needs only to be reduced a few mm.

In the modifications of the device illustrated in FIGS. 5 and 7 to each slide head 24a is provided with a transverse pin 33, the projecting ends of which engage two oppositely arranged grooves 34 provided in the side walls 35 of the grooves 25a. This has the purpose that when the cone 26 is moved against the action of the spring 28 towards the left according to FIG. 5, that then the slide heads 24a are also pulled toward the left. In fact, it is sufficient when only a single leg 12 is pressed inwardly in this manner in order to cause all other legs 12 to move inwardly in the same direction. In the embodiment of the device as shown in FIGS. 1 and 2 or 3 and 4, the legs 12 are moved solely with the cone 26 towards the right in order to be spread uniformly .outwardly but the legs 12 do not follow the movement of the cone 26 towards the left and a collapsing of the linkage parallelograms does not take place positively.

In the modificition of the device of the invention as shown in FIG. 8, the rigid arms 15 and 16 of the prior embodiments are replaced by yieldable arms 15a and 16a which are formed by leaf springs the inner ends of which are attached to the bearing members 3a and the hub 21a, respectively, while the other or outer ends of the leaf springs are attached to the legs 12 by forming spring joints 13a and 14a, 17a and 18a. In FIG. 8 the lower leg 12 of the winding support 11 is illustrated in the rest position and the upper leg 12 is illustrated in the position in which the winding support has the smallest diameter. The modification of the device of the invention as shown in FIG. 8 is particularly recommended for unwinding devices provided with more than three legs because the leaf springs 15a and 16a require less space in circumferential direction than the arms 15 and 16 with their associated hinged joints and, furthermore, leaf springs are less expensive. If desired the legs 12 may be provided with light waves in order to avoid a slidable movement of the thread windings during the unwinding operation.

In place of employing a tubular shaft 1 as shown in FIG. 1 and mounting it on an inner solid shaft 10 which is provided at its free end with a ball bearing 9, it is believed to be obvious that the tubular shaft may also be supported on an inner shaft which is supported at both ends. If this is done, one sacrifices the advantage that one may apply or slip on the thread winding or a winding sleeve of the same without removing a part of the device. This is also true when one rotatably supports the tubular shaft 1 or in place thereof a solid shaft of the same diameter on both ends in two stationary bearmgs.

FIG. 9 illustrates an embodiment of the device of the invention which does not have a tubular shaft. The winding support 11 and the cone 26 are mounted in the same manner as described heretofore, on a shaft 40 which is only supported at one of its ends. The shaft 40 is provided with a reduced bearing pin 41 which carries two axially spaced ball bearings 42 arranged in a flanged tubular bearing body 43. The outwardly extending flange of this tubular bearing body 43 has mounted on one of its faces resilient bodies, such as rubber bumpers, urged against the flange of a fixed bearing body 44 so as to dampen or absorb any oscillations which may occur.

What I claim is:

l. A device for unwinding thread windings comprising a rotatable mountable hollow shaft having a pair of axially spaced hubs mounted thereon, a cone slidably received on one end of said shaft, said cone having a guide surface terminating in a stop, a winding support formed by a plurality of legs extending parallel to said shaft, each leg being connected to the shaft by a pair of arms of equal length which are hingedly connected to the leg and hingedly connected to said pair of hubs so that each leg remains parallel to the shaft as the pair of arms pivot about their points of connection, each leg at one end having a sliding head engaging said guide surface and movable therealong as the cone is moved axially on said shaft, and a spring for biasing the cone in a direction to move said sliding heads towards the stop to move the legs radially outward from the shaft to increase the diameter of the winding support.

2. A device according to claim 1, wherein said arms are leaf springs having one end attached to the leg and the other end attached to one of the pairs of hubs, said leaf springs forming hinged joints at the respective points of attachment.

3. A device according to claim 1, wherein one of said pair of hubs is disposed at one end of said hollow shaft and includes means for supporting a bearing, said shaft having a body at the other end for supporting a second bearing, said pair of bearings supporting the hollow shaft on an inner shaft, said body providing a support surface for the spring which biases the cone.

4. A device according to claim ll, wherein the stop on said guide surface of said cone is provided by a removable ring member so that the position of said stop may be changed by replacing the ring member with a ring member of a different dimension 5. A device according to claim 1, wherein said guide surface of the cone is provided with sliding grooves for each of said sliding heads, each sliding groove having a pair of side walls with each wall of the pair of side walls having a groove for receiving an end of a pin carried by the sliding head. 

1. A device for unwinding thread windings comprising a rotatable mountable hollow shaft having a pair of axially spaced hubs mounted thereon, a cone slidably received on one end of said shaft, said cone having a guide surface terminating in a stop, a winding support formed by a plurality of legs extending parallel to said shaft, each leg being connected to the shaft by a pair of arms of equal length which are hingedly connected to the leg and hingedly connected to said pair of hubs so that each leg remains parallel to the shaft as the pair of arms pivot about their points of connection, each leg at one end having a sliding head engaging said guide surface and movable therealong as the cone is moved axially on said shaft, and a spring for biasing the cone in a direction to move said sliding heads towards the stop to move the legs radially outward from the shaft to increase the diameter of the winding support.
 2. A device according to claim 1, wherein said arms are leaf springs having one end attached to the leg and the other end attached to one of the pairs of hubs, said leaf springs forming hinged joints at the respective points of attachment.
 3. A device according to claim 1, wherein one of said pair of hubs is disposed at one end of said hollow shaft and includes means for supporting a bearing, said shaft having a body at the other end for supporting a second bearing, said pair of bearings supporting the hollow shaft on an inner shaft, said body providing a support surface for the spring which biases the cone.
 4. A device according to claim 1, wherein the stop on said guide surface of said cone is provided by a removable ring member so that the position of said stop may be changed by replacing the ring member with a ring member of a different dimension.
 5. A device according to claim 1, wherein said guide surface of the cone is provided with sliding grooves for each of said sliding heads, each sliding groove having a pair of side walls with each wall of the pair of side walls having a groove for receiving an end of a pin carried by the sliding head. 